Using a gonadotropin-releasing hormone (GnRH) analog, [D-Ser (tBu⁶)] des-Gly¹⁰-GnRH-N-ethlamide (GnRHa) as a ligand the binding capacity of the rat ovary to GnRH during sexual maturation and the mechanism regulating GnRH binding capacity were examined.
Specific high affinity binding sites for GnRH were observed in the ovary and the Kd values for the granulosa cells and the residual tissue were similar to those of whole ovary. During sexual maturation, the GnRH binding capacity of the ovary rose from 7 days of age to a peak at 28 days and declined during the prepubertal period. The treatment with PMSG decreased GnRH binding capacity in the residual tissue as well as in the whole ovary but did not change the binding capacity in the granulosa cells in diethylstilbestrol (DES) primed hypophysectomized rats. Repeated injections of GnRH caused a significant increase in the number of GnRH receptors of the ovary in PMSG treated DES primed hypophysectomized rats but not in the saline treated rat. The granulosa cells exhibited increases in GnRH binding capacity following repeated administrations of GnRH more than the residual tissue did. In GnRH treated DES primed hypophysectomized rats, increasing doses of PMSG increased the binding capacity in the granulosa cells but decreased the binding capacity in the residual tissue.
From these findings, GnRH in combination with PMSG seems to have stimulatory effects on GnRH binding capacity and to increase the sensitivity to GnRH in the granulosa cells.

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Responses of plasma pancreatic polypeptide (PP), glucagon (IRG) and insulin (IRI) after administration of beef soup were studied in normal and alloxan diabetic dogs and their regional content in the pancreas was determined in normal and four or twelve weeks alloxan diabetic dogs. Plasma PP levels of the diabetic dogs were significantly higher than those of the normal dogs and they increased after beef soup administration in both groups. Higher levels of IRG were also found in the diabetic dogs, although IRG increased significantly after beef soup ingestion only in normal dogs. The amounts of PP in the pancreas of normal and diabetic dogs were greatest at the uncinate process, followed in order by the head, body and tail. The IRG content in the pancreas was highest at the tail and lowest at the uncinate process in both dogs. The differences in both PP and IRG in pancreas between normal and diabetic dogs kept in a poor metabolic state for one or three months were not significant in any region of the pancreas. Immunocytochemical studies also suggested these findings. These results show that, irrespective of high plasma levels of PP and IRG in the diabetic dogs, their levels in the pancreas did not change significantly as also indicated by histological studies.

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Following long-term castration of male rats (for 3, 6, 12 and 18 months), some populations of five gonadotroph types, i. e., immature cell, types III, III/IV, IV and so-called signet-ring cell, appeared in the pituitary glands. Their ultrastructures were electron microscopically observed after immunohistochemical identification of them using anti-rat LHβ serum. In unoperated control rats, 60 days old, the predominant III/IV type was intermingled with some populations of III and IV types, but no immature LH cells or signet-ring cells were detected among them. In the present observation not all of the gonadotroph types turned into signet-ring cells. Immature small LH cells containing a few small secretory granules began to appear (2.0%) at 3 months, and had increased to a maximum (52.5%) at 18 months. The percentage of the signetring cells was high (24.1%) at 3 months, but reduced (2.4%) at 18 months. High populations of small, oval and immature LH cells are assumed to occur as a consequence of mitotic division of the most of immature LH cells. This may compensate for the loss of signet-ring cells in order to maintain the high serum LH and FSH concentrations after long-term castration.

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1, 25-dihydroxyvitamin D production in response to two successive infusions of synthetic active 1-34 fragment of human PTH [hPTH-(1-34)] was evaluated in order to develop an understanding of the vitamin D metabolism and the rationale of vitamin D therapy in calcium disorders. Five normal controls, six hypoparathyroid patients, two patients with hypophosphatemic vitamin-Dresistant rickets, one patient with Lowe's synd. and one patient with primary Fanconi's synd. were investigated, and the following results were obtained.
All normal controls showed a significant increase in serum 1, 25 (OH) 2D [43± 3.8 (m± SEM, n=5, basal), 53±4.3 (three hours after the first PTH infusion), 65±7.7 (six hours) and 66±4.4 (nine hours) pg/ml]. All patients with PTHdeficient hypoparathyroidism showed a significant increase in serum 1, 25 (OH) ₂D, and serum 1, 25 (OH) 2D values were within the normal range after hPTH-(1-34) stimulation. Serum 1, 25 (OH) ₂D remained low after hPTH-(1-34) infusions in a patient with pseudohypoparathyroidism type I who showed a significant increase in this value after infusion of dibutyryl cyclic AMP. On the other hand, a patient with normocalcemic pseudohypoparathyroidism type I had a high basal 1, 25 (OH) ₂D value, which increased further after hPTH-(1-34) infusions. An almost normal increase in serum 1, 25 (OH) ₂D was observed in two patients with hypophosphatemic vitamin-D-resistant rickets, one with Lowe's syndrome and the other with primary Franconi's syndrome.
We conclude that these results are important in obtaining an understanding of calcium and vitamin D metabolism in these disorders and that this PTH stimulation test is a useful method to use in evaluating renal responsiveness in 1, 25 (OH) ₂D production to PTH in various calcium disorders.

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A case of a huge inoperable adrenocortical carcinoma which secreted testosterone without characteristic symptoms was treated with o, p'-DDD (2, 2-bis (2-chlorophenyl-4 cholorophenyl) 1, 1-dichloroethane). With this therapy, the tumor decreased in size which was confirmed by the computed tomography (CT). Eighteen months later, however, lethargy and logopathy appeared and the tumor grew again rapidly with the withdrawal of o, p'-DDD performed for the evaluation of these mental disturbances. The tumor then diminished gradually in size soon after the treatment was resumed and the above unfavorable symptoms were not developed again with the combined administration of a central nervous stimulant.
During o, p'-DDD treatment, plasma testosterone and estrogen decreased, and plasma aldosterone also decreased but within the normal range. Plasma cortisol also tended to decrease despite hydrocortisone was administered. Plasma adrenocorticotropic hormone (ACTH) was maintained within the normal range for the first six months but then increased gradually. It decreased and became normal with the additional administration of hydrocortisone.
The patient's normal menstruation at the preadministrative stage changed to oligomenorrhea, then amenorrhea after the treatment, but no endocrinological sign except for the menses was observed during the treatment.

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Inhibin activity in ovarian venous plasma and concentrations of FSH and LH in peripheral plasma were examined in rats during pregnancy, pseudopregnancy and lactation and correlated with the status of the ovarian follicular population. Inhibin activity was assessed in terms of its ability to suppress the 48 h secretion of FSH in a dispersed anterior pituitary cell culture system. FSH and LH were measured by radioimmunoassay.
Inhibin activity in ovarian venous plasma was always detected when Graafian follicles were present, such as Days 3, 5 and 10 of pseudopregnancy, Days 5, 10, 20 and 21 of pregnancy, Days 3, 5 and 10 of lactation in mothers with 2 pups and Days 0, 10, 15 and 20 of lactation in mothers with 8 pups. Inhibin activity in ovarian venous plasma was undetectable whenever healthy antral follicles were absent, such as Day 15 of pregnancy and Days 2, 3, 4 and 5 in lactating rats with 8 pups. No FSH surge occurred during these periods of low inhibin activity in ovarian venous plasma, in striking contrast to normal cyclic rats.
These results indicate that inhibin activity in ovarian venous plasma of rats varies with the number of healthy antral follicles during the luteal phase. Ovarian inhibin in conjunction with other factors such as steroid hormones or the suckling stimulus may be involved in the regulation of FSH secretion in the luteal phase of the rat.

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We describe a 29-year-old male with thyroid hormone resistance. He was first seen because of a goiter, and was considered to have hyperthyroid Graves' disease. Despite subtotal thyroidectomy followed by radioiodine therapy, serum thyroxine levels were elevated with high serum TSH levels. Baseline thyroid function showed serum thyroxine of 16.6μg/dl, free thyroxine of 4.60 ng/dl, triiodothyronine of 197 ng/dl, and TSH of 34μU/ml. Triiodothyronine administration by gradually increased doses of 75, 150, 225, 300, and 375μg/d over a 25-day period resulted in gradual reduction of serum TSH and T4 levels, but serum TSH still responded to TRH even during this period. The basal metabolic rate was-14% and showed a minimal rise even with large doses of triiodothyronine. The results led to the diagnosis of generalized thyroid hormone resistance including the pituitary gland. Increased pulse rate, finger tremor and emotional lability in the patient suggest that the severity of peripheral refractoriness to the hormone may vary from tissue to tissue. In addition, a reduced thyroidal responsiveness to TSH as a consequence of inappropriate radioiodine therapy was observed in this patient.

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An extract of porcine thyroid gland in 0.1 N acetic acid exerted dosedependent potentiation of ACTH-induced corticosterone production in isolated rat adrenal cells. The extract by itself manifested no steroidogenic activity.
Upon gel-filtration of the extract, potentiating activities were demonstrated in three main peaks with molecular weights of about 10, 000, 5, 000 and 2, 000. These findings indicate the presence of heterogeneous forms of ACTH-potentiating factors in the thyroid. Significant enhancement of ACTH-induced steroidogenesis was readily apparent with three gel-filtration fractions at a lower concentration of ACTH (4.75 pM). At this concentration, dose-dependent potentiation was observed with these three fractions.
Enhanced corticosterone production responses by cells preincubated with the thyroid extract were observed and the results indicated the existence of potentiating mechanisms other than inhibition of ACTH proteolysis.
The lack of T₄, T₃ and thyroglobulin in this activity suggests that the activity resides in other constituents of the thyroid.

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Serum thyroid hormone and TSH concentrations were measured before and after the administration of TRH (10μg/kg body weight) and bovine TSH (10 IU) in 14 children with chronic lymphocytic thyroiditis.
The TRH test showed that the responsiveness of TSH was positively correlated with the basal TSH (P<0.001) and inversely with the increase in serum thyroid hormones, for ΔT3 (P<0.05) and for ΔT4 (P<0.001). Overall, the patients had significantly lower mean values for basal T4, but not for T3.
The TSH test revealed that the ΔT3 was positively correlated with ΔT4 (P<0.05).ΔT3 after TSH administration was positively correlated with it after TRH (P<0.05).
The patients were divided into three groups on the basis of their peak TSH values after TRH administration. In Group 1 (peak value below 40 μU/ml; N=5); T3 increased significantly after TRH and TSH administrations (P<0.05 and P<0.025, respectively). In addition, ΔT4 was significant after TSH administration. In Group 2 (peak TSH above 40 and less than 100 μU/ml; N=6); only ΔT3 after TRH was significant (P<0.05). In Group 3 (peak TSH above 100 μU/ml; N=3); the response of thyroid hormones was blunted. Thus, the thyroid hormone responses to endogenous TSH coincided with that to exogenous TSH, and the exaggerated TSH response to TRH indicates decreased thyroid reserve.

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In order to investigate the role of ADH and the renal handling of sodium and water in patients with idiopathic edema, 21 patients were subjected to acute oral water load tests. Although a normal water diuresis was observed in all patients in supine posture, it was markedly impaired in upright posture with significant decreases in sodium, free water, and osmolar clearances. In particular, two patients exihibited the continuous production of concentrated urine after the water load in upright posture. The fractional reabsorption of sodium at the proximal tubules was significantly increased in upright posture, while the glomerular filtration rate did not change significantly. The constricting of both legs with elastic bandages tended to improve the water diuresis in upright posture, suggesting that the pooling of blood into the lower legs might be contributing to the formation of idiopathic edema. The patients showed normal osmoregulation of ADH release in supine, but not in upright posture: the suppression of ADH release in upright posture was only transient or incomplete despite a sufficient fall in plasma osmolality following the water load. Thus, both an increase in renal sodium reabsorption and the insufficient suppression of ADH release in upright posture might contribute to the retention of body fluid in patients with idiopathic edema.

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Factors which specifically inhibit ³H-dexamethasone binding to unoccupied glucocorticoid receptors were examined in cytosols of the seminal vesicle and ventral prostate of rats. The inhibiting factors are mostly precipitated at 40-50% saturation of (NH₄) ₂SO₄ and eluted from a Sephacryl S-200 column immediately after the elution volume of bovine serum albumin. The inhibitory activity was relatively heat-stable and decreased to approximately 35% of the initial activity by trypsin digestion. These results suggest that the inhibiting factors are of a polypeptide-like nature. The inhibitory activity of the factors seems to be blocked by treatment with dithiothreitol and molybdate. The inhibiting factors act to decrease the binding affinity of glucocorticoid receptors to ³H-dexamethasone without altering the number of the available binding sites in cytosols. These results indicate that the binding of glucocorticoid receptors to ligands in vitro is influenced by a number of factors.

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An abnormal hyperresponse of GH to intravenous injection of TRH in a 66-year-old female pellagra patient with typical 3'D's was reported. Diagnosis of pellagra was mainly based on her clinical course and manifestations, although serum levels of nicotinic acid and serotonin were within the normal range. Serum vitamin A and B₂ levels were low. However, these findings did not exclude the diagnosis. The abnormal GH response to TRH observed in this patient was decreased at 2 months and thoroughly disappeared at 10 months after admission. GH response to arginine showed an exaggerated and sustained response on admission, decreased at 2 months and showed an almost normal pattern at 10 months after admission. TSH and prolactin response to TRH were normal throughout the clinical course. LH and FSH response to LH-RH were exaggerated, suggesting post-menopausal hypogonadism. Cortisol response to ACTH showed slightly sustained reactions at both times of the provocation. Oral glucose tolerance test revealed a slight impairment in this patient. These results suggest that pellagra is one of the disorders which exhibit an abnormal hyperresponse of GH to intravenous administration of TRH.

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³H-Dexamethasone binding sites with a K_d of -0.7 nM and a maximum number of binding sites of -0.3 pmoles/mg protein were demonstrated in the uterine cytosol of adrenalectomized rats only if dithiothreitol was present in the incubation mixture and the simultaneous presence of molybdate further enhanced the binding in the cytosol. The binding sites exhibited a high specificity for glucocorticoids and were depleted in a dose-dependent manner from cytosol after administration of dexamethasone to animals. The depletion was not due to the occupation of the binding sites by the dexamethasone administered and the rate of depletion was correlated with the inhibition of uterine growth induced by estrogen administration. The cytosol labeled with 3Hdexamethasone in the presence of dithiothreitol bound to DNA-cellulose efficiently after heating at 25°C for 30 min and the binding was inhibited by pyridoxal 5'-phosphate added to the reaction mixture. The effect of heating on the DNA-cellulose binding was abolished by molybdate in the incubation mixture.
From these observations, it was concluded that ³H-dexamethasone binding sites in the rat uterus were physiologically active glucocorticoid receptors.

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Glycosaminoglycan (GAG) was extracted from thyroid tissue obtained at surgery for thyroid adenoma and adenocarcinoma and compared with that extracted from the thyroid tissue obtained at autopsy of non-thyroid disease. The amount of GAG was almost doubled in thyroid adenoma and increased from 6 to 15 fold in adenocarcinoma when compared with that of apparently normal thyroid tissue. Analysis by Sepharose 2B or 6B column chromatography revealed that at least a part of the GAG in thyroid carcinoma tissue was present in macromolecule form and the molecular size became smaller when treated with papain or alkaline borohydride. The results indicated that those fractions of GAG were present as proteoglycans. The GAG was composed of a mixture of heparan sulfate and chondroitin sulfate or dermatan sulfate in one carcinoma tissue and mainly composed of chondroitin sulfate or dermatan sulfate in the other. The mechanism of the increase in proteoglycan and GAG remains to be elucidated.

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This study has examined an approach to searching for specific proteins associated with the altered nucleosome structure of transcriptionally active genes that are induced by steroid hormones in the hen oviduct. Hen oviduct nuclei were digested with micrococcal nuclease by the procedure which selectively excises nucleosomes from the ovalbumin gene. The oviduct nuclei, as well as chick erythrocyte nuclei, were also digested with DNAase I under conditions preferentially sensitive to the ovalbumin gene, as well as the globin gene. Released proteins were characterized by one- and two-dimensional polyacrylamide gel electrophoresis with detection by silver staining. Thus, high mobility group (HMG) proteins 14 and 17 were found in the three cases of nuclease digestion. Furthermore, about 10, 20 and 15 nonhistone protein spots, specific to each nuclease action, were observed in the cases of micrococcal nuclease to oviduct nuclei and DNAase I to oviduct and erythrocyte nuclei, respectively. Between these three series of protein spots, at least three spots were characterized to be common to those released by both nucleases from oviduct nuclei. These common proteins may be involved, as estrogen receptor proteins or others, in recognition of the ovalbumin DNA sequences, followed by a non-sequence-specific process in which the HMG proteins alter the structure of nucleosomes along the transcription unit.

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